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91.
Background: Recently, various studies have questioned the efficacy of intraoperative acute normovolemic hemodilution (ANH) in reducing bleeding and the need for allogeneic transfusions in cardiac surgery. The aim of the present study was to reevaluate the effects of a low-volume ANH in elective, adult open-heart surgery.

Methods: Two hundred four consecutive adult patients undergoing cardiac surgery were prospectively randomized in a nonblinded manner into two groups: ANH group (103 patients), where 5-8 ml/kg of blood was withdrawn before systemic heparinization and replaced with colloid solutions, and a control group, where no hemodilution was performed (101 patients). Procedures included single and multiple valve surgery, aortic root surgery, coronary surgery combined with valve surgery, or partial left ventriculectomy. The purpose of the study was to evaluate the efficacy of ANH in reducing the need for allogeneic blood components. Routine hematochemical evaluations, perioperative blood loss, major complications, and outcomes were also recorded.

Results: No differences were found between the groups regarding demographics, baseline hematochemical data, and operative characteristics. There was no difference in the amount of transfusions of packed red cells, fresh frozen plasma, platelet concentrates, total number of patients transfused (control group, 36%vs. ANH group, 34.3%;P = 0.88), and amount of postoperative bleeding (control group, 412 ml [313-552 ml]vs. ANH group, 374 ml [255-704 ml]) (median [25th-75th percentiles]);P = 0.94. Further, perioperative complications, postoperative hematochemical data, and outcomes were not different.  相似文献   

92.
PURPOSE: We characterize the consequences of androgen deprivation therapy on body composition in elderly men. MATERIALS AND METHODS: Using a dual energy x-ray absorptiometry instrument, we determined the changes in bone mineral density, bone mineral content, fat body mass and lean body mass in 35 patients with prostate cancer without bone metastases who received luteinizing hormone releasing hormone analogue for 12 months. RESULTS: At baseline conditions 46% of cases were classified as osteopenic and 14% as osteoporotic at the lumbar spine and 40% were osteopenic and 4% osteoporotic at the hip. Androgen deprivation significantly decreased bone mineral density either at the lumbar spine (mean gm./cm.2 [SD] 1.00 [0.194], 0.986 [0.172] and 0.977 [0.182] at baseline, and 6 and 12 months, respectively, p <0.002) or the hip (0.929 [0.136], 0.926 [0.144] and 0.923 [0.138], p <0.03). A more than 2% decrease in bone mineral density was found at the lumbar spine in 19 men (54.3%) and at the hip in 15 (42.9%). Bone mineral content paralleled the bone mineral density pattern. Lean body mass decreased (mean gm. [SD] 50,287 [6,656], 49,296 [6,554] and 49,327 [6,345], p <0.003), whereas fat body mass consistently increased (18,115 [6,209], 20,724 [6,029] and 21,604 [5,923] p <0.001). CONCLUSIONS: Serial bone densitometry evaluation during androgen deprivation therapy may allow the detection of patients with prostate cancer at risk for osteoporotic fractures, that is those with osteopenia or osteoporosis at baseline and fast bone loss. The change in body composition may predispose patients to accidental falls, thus increasing the risk of bone fracture.  相似文献   
93.
BACKGROUND: Bone loss is a frequent and well-known complication in the first months after renal transplantation, but there are no data considering body composition variables (bone, fat, and lean mass) together in transplant recipients. This prospective study investigated total body bone density, fat mass, and lean mass before and 1, 2, 3, 4, and 6 months after renal transplantation in male patients who underwent hemodialysis. METHODS: Twenty consecutive renal transplant male patients aged 23-64 years (mean, 40 years; median, 41 years) received one of two immunosuppressive therapies (cyclosporine+methylprednisolone, or cyclosporine+methylprednisolone+azathioprine). The bone, fat, and lean mass of the total body and its related subregions were assessed by means of dual X-ray photon absorptiometry. Mixed factorial analysis of variance for repeated measurements was used for the statistical analysis. RESULTS: During the 6 months after transplantation, there was a reduction in trabecular bone mass in the spine, ribs, and pelvis total body subregions; the reduction was statistically significant in the last two subregions. There was no statistically significant difference in the lean mass of the total body or its subregions over time, but there was a statistically significant increase in the fat mass of the total body and all of its subregions; the increase in total and trunk fat mass seemed to be greater in the patients not receiving azathioprine. CONCLUSIONS: Up to 6 months after renal transplantation in male patients who underwent hemodialysis, there is a marked increase in fat mass, a significant loss of trabecular bone mass, and no change in cortical bone and lean mass.  相似文献   
94.

Background  

Cervical degenerative pathology produces pain and disability, and if conservative treatment fails, surgery is indicated. The aim of this study was to determined whether anterior decompression and interbody fusion according to Cloward is effective for treating segmental cervical degenerative pathology and whether the results are durable after a 10-year-minimum follow-up.  相似文献   
95.

Background  

Complete removal of all visible lesions is considered the adequate treatment of pelvic endometriosis in order to reduce recurrence. Laparoscopic colorectal resection of bowel endometriosis is still challenging. A large series is reported.  相似文献   
96.

Background

Obstructive left colon carcinoma (OLCC) is a challenging matter in terms of obstruction release as well of oncological issues. Several options are available and no guidelines are established. The paper aims to generate evidenced based recommendations on management of OLCC.

Methods

The PubMed and Cochrane Library databases were queried for publications focusing on OLCC published prior to April 2010. A extensive retrieval, analyses, and grading of the literature was undertaken. The findings of the research were presented and largely discussed among panellist and audience at the Consensus Conference of the World Society of Emergency Surgery (WSES) and Peritoneum and Surgery (PnS) Society held in Bologna July 2010. Comparisons of techniques are presented and final committee recommendation are enounced.

Results

Hartmann's procedure should be preferred to loop colostomy (Grade 2B). Hartmann's procedure offers no survival benefit compared to segmental colonic resection with primary anastomosis (Grade 2C+); Hartmann's procedure should be considered in patients with high surgical risk (Grade 2C). Total colectomy and segmental colectomy with intraoperative colonic irrigation are associated with same mortality/morbidity, however total colectomy is associated with higher rates impaired bowel function (Grade 1A). Segmental resection and primary anastomosis either with manual decompression or intraoperative colonic irrigation are associated with same mortality/morbidity rate (Grade 1A). In palliation stent placement is associated with similar mortality/morbidity rates and shorter hospital stay (Grade 2B). Stents as a bridge to surgery seems associated with lower mortality rate, shorter hospital stay, and a lower colostomy formation rate (Grade 1B).

Conclusions

Loop colostomy and staged procedure should be adopted in case of dramatic scenario, when neoadjuvant therapy could be expected. Hartmann's procedure should be performed in case of high risk of anastomotic dehiscence. Subtotal and total colectomy should be attempted when cecal perforation or in case of synchronous colonic neoplasm. Primary resection and anastomosis with manual decompression seems the procedure of choice. Colonic stents represent the best option when skills are available. The literature power is relatively poor and the existing RCT are often not sufficiently robust in design thus, among 6 possible treatment modalities, only 2 reached the Grade A.  相似文献   
97.
Background Timing of hepatectomy for synchronous metastases of colorectal cancer is still debated. The aim of this retrospective study was to analyze prognostic factors after synchronous and delayed liver resections to define selection criteria for choosing timing of hepatectomy. Methods The study was performed on 127 patients with synchronous metastases undergoing radical hepatectomy. We divided patients according to the timing of hepatectomy: 70 synchronous (group A) and 57 delayed (group B). Results Overall survival was similar between the two groups (5-year survival 30.8% vs. 32.0% A vs. B, P = .406). The multivariate analysis evidenced four independent prognostic factors in group A: male sex (P = .04), T4 (P = .0035), more than three metastases (P = .0001), and metastatic infiltration of nearby structures (P < .0001). There were no statistically significant prognostic factors in group B. Patients with more than three metastases had a significantly worse survival in group A than in group B (3-year survival, 15.0% vs. 34.3%, P = .007); similarly, borderline significant difference was encountered in patients with T4 primary tumor (3-year survival, 16.7% vs. 60%, P = .064) Conclusions Patients with liver metastases synchronous with colorectal cancer with T4 primary tumor, metastasis infiltration of neighboring structures, and especially with more than three metastases should receive neoadjuvant chemotherapy before liver resection.  相似文献   
98.
Objective To evaluate the prognostic significance of different clinico-pathological and molecular factors, and to compare survival after standard and extended pancreaticoduodenectomy (PD) in ampulla of Vater adenocarcinoma (AVAC). Summary Background Data There are discordant data on factors affecting prognosis, and hence therapeutic choices, in AVAC. Patients and Methods Clinical-pathological factors were evaluated in 59 patients, subjected to PD for AVAC; in 42 subjects information on chromosome 17p and 18q allelic losses (LOH) and microsatellite instability (MSI) was also available. The association between survival and type of PD was investigated in the 25 patients operated between 1990 and 2001 (16 standard and nine extended). Results The overall 5- and 10-year tumor-related survival rates were 46% and 33%, respectively. Sixteen patients had T-stages 1–2, 14 T-stage 3, and 29 T-stage 4 cancers. Chromosome 17p and 18q LOH were detected in 23 (55%) and 15 cases (36%), respectively, and in 12 cases (29%) coexisted. Five cases were MSI-positive (12%). At univariate analysis, poor survival was associated with cancer ulceration (P = 0.051), poor differentiation (P = 0.008), T-stage 4 (P < 0.001), nodal metastases (P = 0.004), chromosome 17p (P < 0.001) and 18q LOH (P = 0.002), and absence of MSI (P = 0.009). At multivariate analysis, only T-stage (P = 0.002) and 17p LOH (P = 0.001) were independent predictors of survival. All patients with MSI-positive cancers were long-survivors (>12 yrs), whereas only 30% of MSI-negative cancer patients survived at 5 years. Extended pancreaticoduodenectomy was associated with a 3-year disease-related survival higher than standard resection (83% vs 31%; P = 0.018). Conclusion MSI and chromosome 17p status allow to better define prognosis within ampullary cancers at the same stage. Surgery alone resulted curative in MSI-positive cancer patients, whereas it was inadequate in patients showing allelic losses, who might benefit from adjuvant therapy. In this observational study, extended PD was associated with increased survival compared to standard procedures. Presented at the 2006 Annual Meeting of the American Hepato-Pancreato-Biliary Association, Miami Beach, Florida, March 9–12, 2006  相似文献   
99.
Background The future remnant liver (FRL) limit for safe major hepatectomy with low risk of postoperative liver failure has not yet been well defined. Methods Between April 2000 and September 2004, every patient scheduled for major hepatectomy in our institution underwent CT-volumetry of FRL. Patients with FRL <25% underwent portal vein embolization (PVE). Exclusion criteria were PVE, associated vascular resection and liver cirrhosis. The FRL was correlated with short-term results in patients with normal liver (group A) and those with impaired liver function secondary to neoadjuvant chemotherapy or cholestasis (bilirubin >2 mg/100 ml) (group B). Liver dysfunction was defined as both PT <50% and serum bilirubin level >5 mg/100 ml for three or more consecutive days. Results A total of 119 patients were analyzed, 72 in group A and 47 in group B. The FRL value was the only significant risk factor for postoperative liver dysfunction in the univariate and multivariate analysis (p = 0.009). The FRL did not correlate with postoperative mortality and morbidity. Bilirubin and prothrombin time (PT) on days 3 and 7 were significantly correlated to FRL in both groups. In group A, patients with postoperative liver dysfunction had a FRL<30% (3 versus 0; p = 0.005). According to receiving operator characteristic (ROC) curve analysis, a FRL value of 26.5% predicted postoperative liver dysfunction with 66.7% sensitivity, 97.1% specificity, 50% positive predictive value (PPV), and 98.5% negative predictive value (NPV). In group B, patients with postoperative liver dysfunction had a FRL <35% (4 versus 0; p = 0.027). According to ROC curve analysis, a FRL value of 31.05% predicted postoperative liver dysfunction with 75% sensitivity, 79.1% specificity, 25% PPV, and 97.1% NPV. Conclusions Hepatectomy can be considered safe when FRL is >26.5% in patients with healthy liver and >31% in patients with impaired liver function.  相似文献   
100.
The mechanisms by which aging induces muscle impairment are not well understood yet. We studied the impact of aging on Ca2+ homeostasis in the slow-twitch soleus and the fast-twitch extensor digitorum longus (EDL) muscles of aged rats by using the fura-2 fluorescent probe. In both muscles aging increases the resting cytosolic calcium concentration ([Ca2+]i). This effect was independent on calcium influx since a reduced resting permeability of sarcolemma to divalent cations was observed in aged muscles likely due to a reduced activity of leak channels. Importantly the effects of aging on resting [Ca2+]i, fiber diameter, mechanical threshold and sarcolemmal resting conductances were less pronounced in the soleus muscle, suggesting that muscle impairment may be less dependent on [Ca2+]i in the slow-twitch muscle. The treatment of aged rats with growth hormone restored the resting [Ca2+]i toward adult values in both muscles. Thus, an increase of resting [Ca2+]i may contribute to muscle weakness associated with aging and may be considered for developing new therapeutic strategies in the elderly.  相似文献   
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